Need help figuring out how to graph a rational function with limits? Learn how to graph a rational function using limits to find discontinuities and functional asymptotes with this free video lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test).